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%I #18 Dec 25 2021 18:35:23
%S 31,35,43,50,55,65,76,89,106,113,118,128,139,152,160,167,181,191,202,
%T 206,214,221,226,236,247,260,268,284,298,317,328,341,349,365,379,398,
%U 418,431,439,455,469,488,508,521,529,545,559,578,598,620,628,644,658
%N a(1) = 31; a(n+1) = a(n) + sum of decimal digits of a(n).
%C Elements >= 214 can be found in A007618
%D D. R. Kaprekar, The Mathematics of the New Self Numbers, Privately Printed, 311 Devlali Camp, Devlali, India, 1963.
%H Harvey P. Dale, <a href="/A036228/b036228.txt">Table of n, a(n) for n = 1..1000</a>
%H D. R. Kaprekar, <a href="/A003052/a003052_2.pdf">The Mathematics of the New Self Numbers</a> [annotated and scanned]
%H <a href="/index/Coi#Colombian">Index entries for Colombian or self numbers and related sequences</a>
%t NestList[#+Total[IntegerDigits[#]]&,31,60] (* _Harvey P. Dale_, Jan 30 2020 *)
%Y Cf. A004207, A016052, A007618, A006507, A016052, A249043.
%K easy,nonn,base
%O 1,1
%A Miklos SZABO (mike(AT)ludens.elte.hu)
%E Edited by _Charles R Greathouse IV_, Aug 02 2010